Tag Archives: Bahamas Marine Conservation

BLUE CHROMIS: A FLASH OF COLOUR ON THE REEF

I’ve gone pictorial for today because I have only got my phone with me while we are away. Composition is slow, close to decomposition – and the comms connection is close to disconnection

Blue chromis (Chromis cyaneus) belong to the same group of fishes as damselfishes. These unmistakeable, bright reef denizens are very visible despite their tiny size. These fish are shoalers, so out on the reef you can enjoy them flickering around you as you swim along or hang in the water to admire the corals.

Like many a pretty and easily captured small fish that can be monetised once removed from its natural home environment, the blue chromis is popular for aquariums, and for humans to keep in their own home environments, unselfishly feeding them concocted food.

Blue chromis are adaptable and sociable, and will happily swim with other small reef fishes (as above). My own favourite combo is chromis mixed in with sergeant majors. But a shoal of them (mostly) alone is pretty special too….

I cynically mentioned ‘concocted’ food earlier. Here is one online care instruction for looking after them: “They are omnivores, meaning that they eat both meaty and plant based foods. They are not difficult to feed and will eat a variety of regular aquarium fare, frozen, live, and sometimes even dry food. Feeding them a variety of foods will help them retain their color in captivity. They sometimes feed on the algae in the tank”.

If you are tempted to rescue some from their reef habitat, rest assured that: They have been known to spawn in captivity. Blue chromis can usually be obtained for about $10-15. And don’t hold back on the frozen food (though maybe warm it up a bit before feeding time).

BABY SPERM WHALE IN BAHAMAS WATERS: AMAZING FOOTAGE

Over several years I have had the privilege of being able to feature wonderful photographs and video footage in this blog. Birds, course, and also reef fish, sharks, seahorses, coral and anemones and a whole lot more. I have also been involved throughout with the wonderful work of the Bahamas Marine Mammal Research Organisation (BMMRO),and have been a part of team since 2017. Abaco is lucky enough to have the HQ at Sandy Point, but we must keep in mind that the organisation’s remit extends throughout the entire Bahamas archipelago, and has firm links with research and conservation organisations on the other islands.

The clear turquoise waters around the islands and their cays are well-known to, and appreciated by, all. This is the playground of the smaller marine mammals – the dolphins, smaller whales and the (now a significant presence) manatees.

Less well known are the denizens of the deeper waters and the immense depths of the GREAT BAHAMA CANYONof the northern Bahamas. This is the realm of the large marine animals, from the mysterious speciality beaked whales right up to massive sperm whales.

About 3 weeks ago, the BMMRO research team encountered something truly wondrous off the south Abaco coastline – something to quicken the pulse and gladden the heart – a newborn sperm whale investigating the underwater world it has just been born into. Hopefully it will flourish and live for decades. The hope is sadly tempered by the overwhelming – and increasing – evidence of the terrible effect that humans have caused in just one generation by the pollution of air, land and sea.

Charlotte Dunn posted the footage of 2 separate sightings. Her first caption reads:

“Close encounter with a curious newborn (‘neonate’) sperm whale yesterday – reminding us of the importance of our Shared Waters project about the effects of ship traffic on resident sperm whales, http://www.bahamaswhales.org/research.aspx. The young individuals like this one will be the most impacted if we don’t make serious conservation changes. As this young whale matures, the policy changes we make in the Bahamas now will affect its survival”.

“While their mothers are feeding at depth (knocking sound in the background) this newborn is being cared for by a slightly older calf until the adults return.”

After the second encounter, Charlotte wrote: “Here’s another amazing short clip of the neonate sperm whale we videoed off south Abaco two weeks ago – thank you to the BEP Foundation and the Devereux Ocean Foundation for funding some of our important work with sperm whales in the Bahamas”.

On Charlotte’s conservation points above, over the last 3 months or so I have been checking daily for posts and articles specifically related to stranded, dead, and killed whales, and their stomach contents as revealed by necropsies. I have collected images from around the world. I won’t wreck this marvellous find in Abaco waters by including any of these. This casual research reveals a horrifying attrition rate for marine mammals. Most animals were full of plastics, from micro through flip-flops all the way up to very large chunks. Some of this junk clearly was the actual cause of death rather than a contributing factor. A whale may take several weeks to die in this way. All of it is entirely the responsibility of mankind – and pretty much caused in the last 50 years.

So let’s enjoy this little sperm whale, and hope it grows to an adulthood that will have seen a radical change for the better in its birth environment – the one that should never have been considered ours to destroy.

CREDITS: Brilliant close-up footage plus the clips I have taken from it – Charlotte Dunn / Diane Claridge / BMMRO.

DONATE: If you are touched by the magic of this little Bahamas sperm whale, may I invite you to consider making a donation to BMMRO for its research and conservation work – a scientific commitment that reaches far beyond the waters of the Bahamas. The system is set up to process donations from just $10 upwards, and every cent is used to further the work of BMMRO. Please click the logo below to reach the right page directly.

DOLPHINS IN THE SEA OF ABACO: PLAYTIME

Earlier this year, the team at Friends of the Environment in Marsh Harbour Abaco, in conjunction with BMMRO (Bahamas Marine Mammal Research Organisation), arranged a fundraising trip to look for whales and dolphins. On both counts, the guests’ hopes and expectations were amply fulfilled – in fact, almost certainly exceeded.

Where there is a single dolphin, there will almost invariably be others – and so it proved. The group of bottlenose dolphins turned out to be in a very playful mode, living up to their reputation as delightful, inquisitive, entertainers.

One of the dolphins turned out to be a young 3rd generation animal from the same family, recently weaned. The BMMRO has a large photographic library of dolphins and whales, collected over many years. In the photo above, you’ll see that the dorsal fin of the nearest one is ragged, especially near the top. This is the primary method by which individual animals are recorded to assist with subsequent identification in the field (= water) or back at base in Sandy Point by means of the photo archive.

The trip was perfected when a young female sperm whale came close to the boat… and then rolled onto her side, flipper up, to get a good look at the boat and its human contents. A wonderful experience for all those on board.

MEET ARNOLD: BE A BAHAMAS BLACK GROUPER GROUPIE

The Black Grouper, like all its cousins, has the twin disadvantages of being fished for sport and fished for food. As demand for grouper on the menu rises, so does its vulnerability. The species is described as a ‘slow breeder’, so a depleting population has less chance of sustaining numbers. The consequence is an exponentially diminishing stock of the species. The equation is simple: fewer fish means less and less stock replenishment.

Formerly plentiful, these groupers (like other grouper species) have moved from an IUCN listing of ‘Least Concern’ to ‘Near-Threatened’. Whatever effect climate change may be having on the oceans, stock depletion of this noble species also has more direct human causes.

An adult black grouper’s diet consists of small fish and squid. Juveniles feed primarily on crustaceans. However, certain tiny reef fish – blennies and gobies for example – are important to the species as ‘cleaners’. You can read about their significance by clicking CLEANING STATIONS.

The service performed by tiny fish on large ones (not only groupers) is an example of a symbiotic relationship known as ‘mutualism’**, in which both parties benefit (the little fishes get gacky bits of grouper to eat). The cleaners are able to do their work inside the gills and even the mouth of the host without being at risk.

The NASSAU GROUPER has a defined and enforced closed season to help maintain numbers. It will be interesting to see if the same protection is eventually extended to the black grouper and indeed to other grouper species.

** The other two types of symbiotic relationship are commensalism, in which only one species benefits while the other is neither helped nor harmed; and parasitism, where one creature (the parasite) gains, while the other (the host) suffers.

FLAMINGO TONGUE SNAILS: DECORATIVE CORAL-DWELLERS

FLAMINGO TONGUE SNAILS Cyphoma gibbous are small marine gastropod molluscs related to cowries. The living animal is brightly coloured and strikingly patterned, but that colour only exists in the ‘live’ parts – the so-called ‘mantle’. The shell itself is usually pale, and characterised by a thick ridge round the middle. These snails live in the tropical waters of the Caribbean and the wider western Atlantic. Whether alive or dead, they are gratifyingly easy to identify.

THE IMPORTANCE OF CORAL

Flamingo tongue snails feed by browsing on soft corals. Often, they will leave tracks behind them on the coral stems as they forage (see image below). But corals are not only food – they provide the ideal sites for the creature’s breeding cycle.

Adult females attach eggs to coral which they have recently fed upon. About 10 days later, the larvae hatch. They eventually settle onto other gorgonian corals such as Sea Fans. Juveniles tend to live on the underside of coral branches, while adults are far more visible and mobile. Where the snail leaves a feeding scar, the corals can regrow the polyps, and therefore the snail’s feeding preference is generally not harmful to the coral.

The principal purpose of the patterned mantle of tissue over the shell is to act as the creature’s breathing apparatus. The tissue absorbs oxygen and releases carbon dioxide. As it has been (unkindly?) described, the mantle is “basically their lungs, stretched out over their rather boring-looking shell”.

THREATS AND DEFENCE

The species, once common, is becoming rarer. The natural predators include hogfish, pufferfish and spiny lobsters, though the spotted mantle provides some defence by being rather unpalatable. Gorgonian corals contain natural toxins, and instead of secreting these after feeding, the snail stores them. This supplements the defence provided by its APOSEMATIC COLORATION, the vivid colour and /or pattern warning sign to predators found in many animal species.

MANKIND’S CONTRIBUTION

It comes as little surprise to learn that man is now considered to be the greatest menace to these little creatures, and the reason for their significant decline in numbers. The threat comes from snorkelers and divers who mistakenly / ignorantly think that the colour of the mantle is the actual shell of the animal, collect up a whole bunch from the reef, and in due course are left with… dead snails and “boring-looking shells” (see photos below). Don’t be a collector; be a protector…

The photos below are of nude flamingo tongue shells from the Delphi Club Collection. Until I read the ‘boring-looking shell’ comment, I believed everyone thought they were rather lovely… I did, anyway. You decide!

PILOT WHALES: “DIVIDED BY A COMMON SEA”

You know the thing about Britain and the US being ‘two Nations divided by a common language’? Among the many august people credited with first coming up with this remark, the leading contenders are Oscar Wilde, George Bernard Shaw and Winston Churchill. Generally, Wilde seems to be considered the winning author**. Whichever, the saying is intended to be lightly and amusingly rude, probably to both nations.

Well, pilot whales are in a similar position. They are found on both sides of the Atlantic (and many other places of course). As acoustic analysis of the sounds made by marine mammals becomes increasingly sophisticated, the evidence suggests that a pilot whale in The Canary Islands saying “Hey guys, meal approaching 11.00 o’clock, moving right, 30 feet” will use different sounds from its counterpart in the Bahamas.

Short-finned pilot whales (Globicephala macrorynchus) are also known as blackfish or potheads (though some may reserve this last term for – ahem – higher species). As with MELON-HEADED WHALES, they are in fact a species of large dolphin. They can grow to nearly 20′ long and weigh accordingly.

Pilot whales live in large pods of 50 or more. These are so-called ‘matrilineal’ groups, meaning that they consist of 2 or even 3 generations of related females. When the sea is calm, they sometimes adopt a behaviour known as ‘logging’, in which they will spend a long time – maybe hours – lying on the surface in tight groups.

In The Bahamas, pilot whales are seen year-round but are more common during the spring and summer months. Some are resident, but Bahama pilot whales appear to have large ranging patterns. Pilot whales tagged in The Bahamas have travelled as far north as North Carolina suggesting they are part of a population located in the US southeast .

HOW DO RESEARCHERS RECOGNISE EACH ANIMAL?

The first place to look is the dorsal fin. There are (at least) two reasons for this. First, it’s the part of the dolphin / whale that is most visible through binoculars; secondly, it is the part that tends to acquire nicks, ragged edges, and scar patterns that are unique to that animal. When a new cetacean is sighted, it is logged and assigned an ID. This will usually be kept simple and scientific: “look, there’s AL16 again” and so on; how unlike birds, where banders assign names such as Felicia Fancybottom, Bahama Mama and Harry Potter.

If you look at #2 above, notice the distinctive hooked dorsal fin of the right-hand pilot of the trio. An easy ID for future sightings. And see below for nicks and scarring.

MEANWHILE, 3643 MILES EAST ACROSS THE ATLANTIC

Last Autumn my niece and her family went to La Gomera, a small volcanic island in the Canaries. They all went on a whale / dolphin watching trip and were delighted to encounter a group of pilot whales. My great nephew, not yet a teenager, had an iphone with him and in the circumstances of standing on a moving platform photographing creatures swimming fast through the water, he did a very good job. A couple of them even have a bonus shearwater.

The west and east Atlantic pilot whales shown here are almost exactly on the same latitude

I’m not particularly bothered by my lack of photographic eptitude, but even I feel that my own shot of a pilot whale in the Sea of Abaco rates high in the list of epic fails

The identity of the photographer is protected under the Official Secrets Act 1989

** ‘We have really everything in common with America nowadays except, of course, language’ Oscar Wilde The Canterville Ghost (1887)

FORAYS WITH MORAYS (6): WELL SPOTTED…

I was always taught ‘keep your mind open and your mouth closed’. Bad advice. Such bad advice. The worst. So many reasons to be exactly the opposite in these troubled times…

Spotted Moray eels Gymnothorax moringa, however, seem to have their own rules to live by. They appear to be open-minded and fairly sensible creatures around the reef. They tend to keep themselves to themselves, hanging out unassumingly in holes and crevices in the coral.

They do tend to stick their necks out a bit, but unless provoked (see below) they seem to be reasonably amiable (except maybe to the small fish and crustaceans that make up their diet).

They do keep their mouths open a lot, though. And as you can see, they have sharp-looking teeth that you mightn’t want too near to you. I say that because their bite can be dangerous and should be avoided. To start with, the teeth are slightly backward-facing, so that when they bite there is a ‘pull-back’ effect when you react (not unlike a barb on a fish hook). They are not aggressive as such, but they know how to deal with unwanted interference in their lives…

Apart from the unpleasant bite and associated pain that moray eels can inflict in defence, they are also poisonous (as opposed to venomous). Specifically they can release toxins into the wound; and in some species their skin contains toxins as well**. Serious infection may result.

CAN YOU GIVE THE POISONOUS / VENOMOUS DISTINCTION AGAIN

I could, but ace natural history cartoonist Rosemary Mosco makes a better job than I can:

**Before I leave the topic, maybe I ought to mention one bit of research I have just come across at Dove Med, from which I take away the message that you definitely don’t want to annoy a moray eel or get bitten by one. Ever. They are fine and interesting denizens of the reef, to be admired from a respectful distance…